Lightning in PvE or PvM situations could be a + or a -.
It depends. If you wanted to kill multiple monsters, lightning would do the job. But if you just want to kill one monster and keep away from the rest, then that's another story.
Lightning in PvP seems to be not as good as fire or ice IMO because fire could give burn and/or extra damage to an opponent. Ice could slow down or freeze other players as well. But high levels usually have immunity.
Im not sure about PvP sorry

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